After 5th round of counselling, there will be internal sliding in all NITs. Seats then lying vaccant would be filled through SPOT counselling. In SPOT counselling you will have to report to the nearest reporting centre and fill your preferences from the available vaccancy.
Last year CBSE conducted 7 rounds of counselling, still most of the NITs ,except the priviledged few, could not draw considerable crowd. SPOT counselling would ensure more transparency in the process,lesser vacant seats in NITs and also higher cut-offs.
Most importanly, private colleges(like LPU and Amity) have not been allowed to participate in CCB before the SPOT Round, so these colleges will have lower cut-offs while NITs and IITs will close down on higher side,